that. but first, does donald trump, do people at the top of the administration, have reason to worry? >> i've spoken to people who have been questioned by mueller's team in recent weeks, more than one, and the sense is that this is deeply, deeply serious, that mueller is becoming more aggressive with his questioning, that they are zeroing in on something, what that something is vague and mueller certainly isn't giving that up, but this isn't child's play. >> and we said a couple days ago peter baker they already seem to have enough evidence to have manafort dead to center. you don't need rick gates to get manafort. he stayed on and helped with the inaugural committee, was there an awful lot. do people above paul manafort have a reason to worry? does donald trump have a reason to worry? and when you say this investigation is gaining steam,